1 /* 2 * HT handling 3 * 4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> 5 * Copyright 2002-2005, Instant802 Networks, Inc. 6 * Copyright 2005-2006, Devicescape Software, Inc. 7 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 8 * Copyright 2007, Michael Wu <flamingice@sourmilk.net> 9 * Copyright 2007-2010, Intel Corporation 10 * Copyright(c) 2015 Intel Deutschland GmbH 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License version 2 as 14 * published by the Free Software Foundation. 15 */ 16 17 /** 18 * DOC: RX A-MPDU aggregation 19 * 20 * Aggregation on the RX side requires only implementing the 21 * @ampdu_action callback that is invoked to start/stop any 22 * block-ack sessions for RX aggregation. 23 * 24 * When RX aggregation is started by the peer, the driver is 25 * notified via @ampdu_action function, with the 26 * %IEEE80211_AMPDU_RX_START action, and may reject the request 27 * in which case a negative response is sent to the peer, if it 28 * accepts it a positive response is sent. 29 * 30 * While the session is active, the device/driver are required 31 * to de-aggregate frames and pass them up one by one to mac80211, 32 * which will handle the reorder buffer. 33 * 34 * When the aggregation session is stopped again by the peer or 35 * ourselves, the driver's @ampdu_action function will be called 36 * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the 37 * call must not fail. 38 */ 39 40 #include <linux/ieee80211.h> 41 #include <linux/slab.h> 42 #include <linux/export.h> 43 #include <net/mac80211.h> 44 #include "ieee80211_i.h" 45 #include "driver-ops.h" 46 47 static void ieee80211_free_tid_rx(struct rcu_head *h) 48 { 49 struct tid_ampdu_rx *tid_rx = 50 container_of(h, struct tid_ampdu_rx, rcu_head); 51 int i; 52 53 for (i = 0; i < tid_rx->buf_size; i++) 54 __skb_queue_purge(&tid_rx->reorder_buf[i]); 55 kfree(tid_rx->reorder_buf); 56 kfree(tid_rx->reorder_time); 57 kfree(tid_rx); 58 } 59 60 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, 61 u16 initiator, u16 reason, bool tx) 62 { 63 struct ieee80211_local *local = sta->local; 64 struct tid_ampdu_rx *tid_rx; 65 struct ieee80211_ampdu_params params = { 66 .sta = &sta->sta, 67 .action = IEEE80211_AMPDU_RX_STOP, 68 .tid = tid, 69 .amsdu = false, 70 .timeout = 0, 71 .ssn = 0, 72 }; 73 74 lockdep_assert_held(&sta->ampdu_mlme.mtx); 75 76 tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid], 77 lockdep_is_held(&sta->ampdu_mlme.mtx)); 78 79 if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid)) 80 return; 81 82 RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL); 83 __clear_bit(tid, sta->ampdu_mlme.agg_session_valid); 84 85 ht_dbg(sta->sdata, 86 "Rx BA session stop requested for %pM tid %u %s reason: %d\n", 87 sta->sta.addr, tid, 88 initiator == WLAN_BACK_RECIPIENT ? "recipient" : "inititator", 89 (int)reason); 90 91 if (drv_ampdu_action(local, sta->sdata, ¶ms)) 92 sdata_info(sta->sdata, 93 "HW problem - can not stop rx aggregation for %pM tid %d\n", 94 sta->sta.addr, tid); 95 96 /* check if this is a self generated aggregation halt */ 97 if (initiator == WLAN_BACK_RECIPIENT && tx) 98 ieee80211_send_delba(sta->sdata, sta->sta.addr, 99 tid, WLAN_BACK_RECIPIENT, reason); 100 101 /* 102 * return here in case tid_rx is not assigned - which will happen if 103 * IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set. 104 */ 105 if (!tid_rx) 106 return; 107 108 del_timer_sync(&tid_rx->session_timer); 109 110 /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */ 111 spin_lock_bh(&tid_rx->reorder_lock); 112 tid_rx->removed = true; 113 spin_unlock_bh(&tid_rx->reorder_lock); 114 del_timer_sync(&tid_rx->reorder_timer); 115 116 call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx); 117 } 118 119 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, 120 u16 initiator, u16 reason, bool tx) 121 { 122 mutex_lock(&sta->ampdu_mlme.mtx); 123 ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx); 124 mutex_unlock(&sta->ampdu_mlme.mtx); 125 } 126 127 void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap, 128 const u8 *addr) 129 { 130 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 131 struct sta_info *sta; 132 int i; 133 134 rcu_read_lock(); 135 sta = sta_info_get_bss(sdata, addr); 136 if (!sta) { 137 rcu_read_unlock(); 138 return; 139 } 140 141 for (i = 0; i < IEEE80211_NUM_TIDS; i++) 142 if (ba_rx_bitmap & BIT(i)) 143 set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested); 144 145 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); 146 rcu_read_unlock(); 147 } 148 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session); 149 150 /* 151 * After accepting the AddBA Request we activated a timer, 152 * resetting it after each frame that arrives from the originator. 153 */ 154 static void sta_rx_agg_session_timer_expired(unsigned long data) 155 { 156 /* not an elegant detour, but there is no choice as the timer passes 157 * only one argument, and various sta_info are needed here, so init 158 * flow in sta_info_create gives the TID as data, while the timer_to_id 159 * array gives the sta through container_of */ 160 u8 *ptid = (u8 *)data; 161 u8 *timer_to_id = ptid - *ptid; 162 struct sta_info *sta = container_of(timer_to_id, struct sta_info, 163 timer_to_tid[0]); 164 struct tid_ampdu_rx *tid_rx; 165 unsigned long timeout; 166 167 rcu_read_lock(); 168 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]); 169 if (!tid_rx) { 170 rcu_read_unlock(); 171 return; 172 } 173 174 timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout); 175 if (time_is_after_jiffies(timeout)) { 176 mod_timer(&tid_rx->session_timer, timeout); 177 rcu_read_unlock(); 178 return; 179 } 180 rcu_read_unlock(); 181 182 ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n", 183 sta->sta.addr, (u16)*ptid); 184 185 set_bit(*ptid, sta->ampdu_mlme.tid_rx_timer_expired); 186 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); 187 } 188 189 static void sta_rx_agg_reorder_timer_expired(unsigned long data) 190 { 191 u8 *ptid = (u8 *)data; 192 u8 *timer_to_id = ptid - *ptid; 193 struct sta_info *sta = container_of(timer_to_id, struct sta_info, 194 timer_to_tid[0]); 195 196 rcu_read_lock(); 197 ieee80211_release_reorder_timeout(sta, *ptid); 198 rcu_read_unlock(); 199 } 200 201 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid, 202 u8 dialog_token, u16 status, u16 policy, 203 u16 buf_size, u16 timeout) 204 { 205 struct ieee80211_local *local = sdata->local; 206 struct sk_buff *skb; 207 struct ieee80211_mgmt *mgmt; 208 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU); 209 u16 capab; 210 211 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); 212 if (!skb) 213 return; 214 215 skb_reserve(skb, local->hw.extra_tx_headroom); 216 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24); 217 memset(mgmt, 0, 24); 218 memcpy(mgmt->da, da, ETH_ALEN); 219 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 220 if (sdata->vif.type == NL80211_IFTYPE_AP || 221 sdata->vif.type == NL80211_IFTYPE_AP_VLAN || 222 sdata->vif.type == NL80211_IFTYPE_MESH_POINT) 223 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 224 else if (sdata->vif.type == NL80211_IFTYPE_STATION) 225 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); 226 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 227 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); 228 229 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 230 IEEE80211_STYPE_ACTION); 231 232 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp)); 233 mgmt->u.action.category = WLAN_CATEGORY_BACK; 234 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP; 235 mgmt->u.action.u.addba_resp.dialog_token = dialog_token; 236 237 capab = (u16)(amsdu << 0); /* bit 0 A-MSDU support */ 238 capab |= (u16)(policy << 1); /* bit 1 aggregation policy */ 239 capab |= (u16)(tid << 2); /* bit 5:2 TID number */ 240 capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */ 241 242 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab); 243 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout); 244 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status); 245 246 ieee80211_tx_skb(sdata, skb); 247 } 248 249 void __ieee80211_start_rx_ba_session(struct sta_info *sta, 250 u8 dialog_token, u16 timeout, 251 u16 start_seq_num, u16 ba_policy, u16 tid, 252 u16 buf_size, bool tx, bool auto_seq) 253 { 254 struct ieee80211_local *local = sta->sdata->local; 255 struct tid_ampdu_rx *tid_agg_rx; 256 struct ieee80211_ampdu_params params = { 257 .sta = &sta->sta, 258 .action = IEEE80211_AMPDU_RX_START, 259 .tid = tid, 260 .amsdu = false, 261 .timeout = timeout, 262 .ssn = start_seq_num, 263 }; 264 265 int i, ret = -EOPNOTSUPP; 266 u16 status = WLAN_STATUS_REQUEST_DECLINED; 267 268 if (!sta->sta.ht_cap.ht_supported) { 269 ht_dbg(sta->sdata, 270 "STA %pM erroneously requests BA session on tid %d w/o QoS\n", 271 sta->sta.addr, tid); 272 /* send a response anyway, it's an error case if we get here */ 273 goto end_no_lock; 274 } 275 276 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { 277 ht_dbg(sta->sdata, 278 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n", 279 sta->sta.addr, tid); 280 goto end_no_lock; 281 } 282 283 /* sanity check for incoming parameters: 284 * check if configuration can support the BA policy 285 * and if buffer size does not exceeds max value */ 286 /* XXX: check own ht delayed BA capability?? */ 287 if (((ba_policy != 1) && 288 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) || 289 (buf_size > IEEE80211_MAX_AMPDU_BUF)) { 290 status = WLAN_STATUS_INVALID_QOS_PARAM; 291 ht_dbg_ratelimited(sta->sdata, 292 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n", 293 sta->sta.addr, tid, ba_policy, buf_size); 294 goto end_no_lock; 295 } 296 /* determine default buffer size */ 297 if (buf_size == 0) 298 buf_size = IEEE80211_MAX_AMPDU_BUF; 299 300 /* make sure the size doesn't exceed the maximum supported by the hw */ 301 if (buf_size > local->hw.max_rx_aggregation_subframes) 302 buf_size = local->hw.max_rx_aggregation_subframes; 303 params.buf_size = buf_size; 304 305 /* examine state machine */ 306 mutex_lock(&sta->ampdu_mlme.mtx); 307 308 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) { 309 ht_dbg_ratelimited(sta->sdata, 310 "unexpected AddBA Req from %pM on tid %u\n", 311 sta->sta.addr, tid); 312 313 /* delete existing Rx BA session on the same tid */ 314 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, 315 WLAN_STATUS_UNSPECIFIED_QOS, 316 false); 317 } 318 319 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) { 320 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 321 ht_dbg(sta->sdata, 322 "Rx A-MPDU request on %pM tid %d result %d\n", 323 sta->sta.addr, tid, ret); 324 if (!ret) 325 status = WLAN_STATUS_SUCCESS; 326 goto end; 327 } 328 329 /* prepare A-MPDU MLME for Rx aggregation */ 330 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL); 331 if (!tid_agg_rx) 332 goto end; 333 334 spin_lock_init(&tid_agg_rx->reorder_lock); 335 336 /* rx timer */ 337 tid_agg_rx->session_timer.function = sta_rx_agg_session_timer_expired; 338 tid_agg_rx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid]; 339 init_timer_deferrable(&tid_agg_rx->session_timer); 340 341 /* rx reorder timer */ 342 tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired; 343 tid_agg_rx->reorder_timer.data = (unsigned long)&sta->timer_to_tid[tid]; 344 init_timer(&tid_agg_rx->reorder_timer); 345 346 /* prepare reordering buffer */ 347 tid_agg_rx->reorder_buf = 348 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL); 349 tid_agg_rx->reorder_time = 350 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL); 351 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) { 352 kfree(tid_agg_rx->reorder_buf); 353 kfree(tid_agg_rx->reorder_time); 354 kfree(tid_agg_rx); 355 goto end; 356 } 357 358 for (i = 0; i < buf_size; i++) 359 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]); 360 361 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 362 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n", 363 sta->sta.addr, tid, ret); 364 if (ret) { 365 kfree(tid_agg_rx->reorder_buf); 366 kfree(tid_agg_rx->reorder_time); 367 kfree(tid_agg_rx); 368 goto end; 369 } 370 371 /* update data */ 372 tid_agg_rx->dialog_token = dialog_token; 373 tid_agg_rx->ssn = start_seq_num; 374 tid_agg_rx->head_seq_num = start_seq_num; 375 tid_agg_rx->buf_size = buf_size; 376 tid_agg_rx->timeout = timeout; 377 tid_agg_rx->stored_mpdu_num = 0; 378 tid_agg_rx->auto_seq = auto_seq; 379 tid_agg_rx->reorder_buf_filtered = 0; 380 status = WLAN_STATUS_SUCCESS; 381 382 /* activate it for RX */ 383 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx); 384 385 if (timeout) { 386 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout)); 387 tid_agg_rx->last_rx = jiffies; 388 } 389 390 end: 391 if (status == WLAN_STATUS_SUCCESS) 392 __set_bit(tid, sta->ampdu_mlme.agg_session_valid); 393 mutex_unlock(&sta->ampdu_mlme.mtx); 394 395 end_no_lock: 396 if (tx) 397 ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid, 398 dialog_token, status, 1, buf_size, 399 timeout); 400 } 401 402 void ieee80211_process_addba_request(struct ieee80211_local *local, 403 struct sta_info *sta, 404 struct ieee80211_mgmt *mgmt, 405 size_t len) 406 { 407 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num; 408 u8 dialog_token; 409 410 /* extract session parameters from addba request frame */ 411 dialog_token = mgmt->u.action.u.addba_req.dialog_token; 412 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout); 413 start_seq_num = 414 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4; 415 416 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab); 417 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1; 418 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; 419 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; 420 421 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 422 start_seq_num, ba_policy, tid, 423 buf_size, true, false); 424 } 425 426 void ieee80211_start_rx_ba_session_offl(struct ieee80211_vif *vif, 427 const u8 *addr, u16 tid) 428 { 429 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 430 struct ieee80211_local *local = sdata->local; 431 struct ieee80211_rx_agg *rx_agg; 432 struct sk_buff *skb = dev_alloc_skb(0); 433 434 if (unlikely(!skb)) 435 return; 436 437 rx_agg = (struct ieee80211_rx_agg *) &skb->cb; 438 memcpy(&rx_agg->addr, addr, ETH_ALEN); 439 rx_agg->tid = tid; 440 441 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_START; 442 skb_queue_tail(&sdata->skb_queue, skb); 443 ieee80211_queue_work(&local->hw, &sdata->work); 444 } 445 EXPORT_SYMBOL(ieee80211_start_rx_ba_session_offl); 446 447 void ieee80211_stop_rx_ba_session_offl(struct ieee80211_vif *vif, 448 const u8 *addr, u16 tid) 449 { 450 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 451 struct ieee80211_local *local = sdata->local; 452 struct ieee80211_rx_agg *rx_agg; 453 struct sk_buff *skb = dev_alloc_skb(0); 454 455 if (unlikely(!skb)) 456 return; 457 458 rx_agg = (struct ieee80211_rx_agg *) &skb->cb; 459 memcpy(&rx_agg->addr, addr, ETH_ALEN); 460 rx_agg->tid = tid; 461 462 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_STOP; 463 skb_queue_tail(&sdata->skb_queue, skb); 464 ieee80211_queue_work(&local->hw, &sdata->work); 465 } 466 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session_offl); 467